mmapper allows to access every resource attached to the machine.
It can read and write any physical address on the memory bus, any I/O port and any field of the PCI space configuration of any peripheral.

Currently, the Linux kernel doesn't support three keys on the "Microsoft Natural® Ergonomic Keyboard 4000": the "Spell" function key and the Zoom-/Zoom+ Rocker. This program is a userspace (X11) driver for those three keys.

PK2Aux is a library and suite of command-line utilities for using the Microchip PICkit2 programmer device for purposes other than programming (such as the generic pin controls, serial UART, and logic analyzer modes provided by the Windows software).

A small application that allows the user to control JACK transport via Midi Machine Control (MMC) commands. MMC is a common protocol sent by hard disk recorders and midi control pads to let other devices or programs know where you are in a track.

This is the Linux kernel driver for the stmpe2401 and stmpe2402 GPIO expanders from ST Microelectronics. These i2c chips support up to 24 extra GPIO lines, have 3 programmable PWM outputs, an integrated keypad input, and rotator input controllers.

Genius WizardPen or MousePen tablet open-source driver for X.org and XFree86 4.x based on Acecad Flair tablet driver. It is using Linux kernel evdev module. Various tablets based on same chip (WP8060U) are also supported.